DESCRIPTION: This is a phase II SBIR request for funding of two years of support for the development of simple laboratory methods to diagnosis beta- thalassemia in Southeast Asian and American populations and to explore establishment of reverse Dot Blot methods for Middle Eastern and Asian Indians who have different genetic defects. Phase I efforts were headed with Dr. Pranee Sutcharitchan as Principal Investigator. The new Principal Investigator, Gerald L. Kropp has been working closely with Dr. Sutcharitchan throughout phase I of the project. During phase I of this proposal, the group successfully developed a method based on the polymerase chain reaction to detect specific DNA mutations of individuals with beta-thalassemia using a single hybridization reaction. The Dot Blot method was used and this has the advantage of simplicity so that the methodology could be used in a number of laboratories without significant difficulty. Diagnostic filter kits specific for the mutations found in Thai and African American populations were made and in the current application they propose to test these kits in large populations of patients at risk and develop them for commercial application, first as a referral service and then as marketable kits. They intend to extend the development of kits for other populations afflicted with beta- thalassemia. They plan to begin with Middle Eastern and Asian Indian groups because published data on beta-thalassemia mutations found in this population are already available. In addition, they propose further to perform large scale testing of these kits to develop them also for commercial use. The work will be performed under the leadership of Gerald Kropp and by Dr. Steven Embury at the San Francisco General Hospital from where he will advise the Principal Investigator in establishing the reverse Dot Blot method for Middle Eastern and Asian Indian subjects and obtained controlled DNA samples containing well defined Middle Eastern Indian beta-thalassemia mutations.